Symptom Networks, Developmental Pathways, and Intervention Evidence for Co-occurring Anxiety and Depression in...

Anxiety and depression frequently co-occur in children and adolescents, but studies of their joint presentation use different units of analysis. This scoping review examined how those approaches connect and where evidence remains limited. We searched PubMed, Web of Science Core Collection, Scopus, and APA PsycINFO for English-language studies available from 2010 to 11 May 2026. We mapped 205 eligible studies across eight non-exclusive empirical themes and interpreted their distribution from a developmental perspective. Study designs varied with the constructs examined. Among 52 symptom-network studies, 37 analysed cross-sectional data and 15 used longitudinal or trajectory cohort designs. Only 16 of 170 risk-factor studies also evaluated treatment outcomes. One symptom-network study linked network-derived findings to a neurobiological measure. Developmental and geographical coverage was uneven. Three studies were child-focused, and the United States and China accounted for 69.27% of the evidence. The descriptive Global South aggregate accounted for 5.85%. These patterns identify priorities for longitudinal within-person research, developmental stratification, and studies linking symptom models to biological measures and intervention mechanisms. Locally validated measures and research in underrepresented settings are needed to assess whether findings transfer across populations.